...... The Military guys have known for years that 20 to 30 watts on HF is all that you need even when using short tactical whips on HF manpack radios. If the military could have used 5 watts and make more battery space or light radios they would have have done so a long time ago. They experts at what they do and 20 watts today is considered effective communications power even when special forces operators have to get the message from 1 continent to the other. When the Falklands war was happening I could hear military HF clansman manpack communications all day and all night long . If they were running 5 watts I would have never have heard them from another continent.......
Quite right. I’ve been doing QRP since 1980 when I was on a Special Forces A team. We used AN/PRC-74B HF radios that were rated at 15 watts PEP. Mind you that was for a radio that was powered by a regulated bench power supply and measured with a perfect 50 ohm load in a laboratory. The real power was a lot less in the field with old nicad batteries, especially in the winter time. My guess we got about 6-8 watts out of them on a good day; less on a normal day. And we did 700 mile shots to our base station day in and day out. Some A teams did 1200 miles no issues. And yes, 8 watts is QRP!
We would walk at least 5 kilometers, more like 10 from our base camp to the radio broadcast site, set up the dipole and since we were in Europe, we would tune to RWN (Russia) to check our watches. We would then catch the blind broadcast at 13 WPM Morse from our base station in England. We would then decrypt our frequency from the blind broadcast, drop the antenna, ‘cut’ the dipole to frequency (the number 468 was used all the time!), and get it back up so we could burst out our encrypted Morse messages 15 minutes later. Miss the blind broadcast and you were screwed as you had no idea what frequency to broadcast on. No tune ups, no antenna tuners, no SWR meters, just one shot so you had to do it right. Missing a transmission was bad, very bad. Missing two in a row would cause a lot of people to panic. Missing 3 in a row and emergency resupply air drops would be flown to our E&E DZ.
After we were done we would pack up and walk the 5 kilometers back. Lots of times it was 10 kilometers. The next day we would get our messages in the morning blind broadcast at 13 WPM. The radio operators could copy code at 21 wpm or faster.
Pop Quiz: Why did our base station transmit at 13 WPM when our radio operators could copy at 21 WPM plus?
To me, QRP power levels are relative. If everyone in your net is using 1500 watts and you have only 100 watts you are QRP. If you have 5 watts and everyone else has 1 watt (GMRS for example) you are QRO.
Now a days I just use my FT-817 at 5 watts. If I need to, I kick in the THP 50 watt amp. For me it’s the QSO that matters not the power level.